I'm sorry, but I don't get your point. Common names are not universally used, and are often simply made up by suppliers or aquarium stores. The photos are taken from various websites, which I presume provided scientific names. I think it would add a lot of value to readers if you passed that information on. In any case, providing vague names such as "lungfish" makes the game easier not harder. There are three genera of extant lungfishes in three different continents (my guess is yours is an African lungfish - Protopterus). Similarly, there are freshwater needlefish species in several different parts of the world (my guess is yours is an Asian species, Xenentodon cancilla), numerous freshwater pipefish species (yours looks to be Hippichthys spicifer), several un-related species of freshwater blennies (yours looks like Omobranchus zebra), and the name water cow has been applied to at least two different genera of sleepers (gudgeons) (yours appears to be Eleotris picta).